Greenwire: When Senate Majority Leader Mitch McConnell urged governors nationwide to "just say no" to U.S. EPA's new carbon emissions rules earlier this year, Colorado Gov. John Hickenlooper (D) offered what he called a "thoughtful" response publicly declining the Republican's suggestion. Now he admits that he just couldn't help trolling the Kentucky senator. "It did give me a certain pleasure to write the letter back saying that not only will we work on this but we're going to do it, we're going to do it...